OK I am in a bind. Fixing a machine and can't afford to get some briwax to prevent rusting on the plated parts. However, I did read that 2-3 coats of clear finger nail polish will prevent rust on metal surfaces? Would this be safe or work? Anyone tried it?

I have come across some strange odds and ends that end up with sewing machines from time to time. Some of them I have no idea what they are for. I found a scraper in with a vintage Pfaff a while back and kept it thinking that it didn't go with the sewing machine. The other day I was looking through an attachment box for another vintage Pfaff and found the same scraper. It could be just by chance, but I am thinking that it is not. Can anyone tell me what this tool is for sure and what do you do with it?
~G~